[llvm] [RISCV] Add QingKe "XW" compressed opcode extension (PR #97925)

[Pengcheng Wang via llvm-commits]

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@@ -0,0 +1,188 @@
+//===-- RISCVInstrInfoXwch.td ------------------------------*- tablegen -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This file describes the vendor extension(s) defined by WCH.
+//
+//===----------------------------------------------------------------------===//
+
+class QK_Stack<bits<2> funct2, dag outs, dag ins, string opcodestr, string argstr>
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wangpc-pp wrote:

QK_Stack -> QKStackInst?

https://github.com/llvm/llvm-project/pull/97925